HS2 Ltd has announced a pilot project to repurpose worn-out wind turbine blades for use on the high speed rail project.

The innovation, believed to be a world first, will use suitable sections cut from decommissioned wind turbine blades in reinforced concrete instead of steel rebar.

HS2 Ltd estimates that the world-first project will cut carbon production by up to 90%.

The initiative is being taken forward under HS2 Ltd’s innovation programme by Skanska Costain Strabag joint venture, and the UK’s National Composites Centre, part of the High Value Manufacturing Catapult.

HS2 Ltd innovation manager Rob Cairns said: “Reusing old turbine blades reduces waste, cuts demand for new steel and reduces the carbon generated during the production of concrete.

“This scheme is a brilliant example of the innovation happening on the whole HS2 project. If our world-first pilot project goes well, we could see a waste product from the energy industry becoming an essential material for the construction sector in the future.”

By 2023, around 15,000 turbine blades will have been decommissioned across the UK and EU. Until now, expired blades have either been ground down to be used as building materials or sent to energy-from-waste incinerators.

The innovative project will swap steel rebar, traditionally used to reinforce concrete, with sections of glass fibre reinforced polymer turbine blades that have reached the end of their operational lives generating low carbon electricity.

Skanska Costain Strabag Joint Venture’s innovation manger Harrison O’Hara added: “Wind turbine blades are extremely difficult to recycle. Ideas of what to do with them after they’re taken down range from turning them into playground slides to processing them into pellets for glues and paints.

“What’s potentially so significant about this innovation is that unlike some other turbine blade recycling initiatives, which involve reprocessing, our innovation reinforces concrete with sections simply cut from the turbines – massively reducing the carbon produced in repurposing the blades.”

NCC head of construction and infrastructure Graeme Jeremy added: “We’re looking forward to supporting this project. Composite materials offer huge benefits to a number of different industries, and finding new, sustainable uses for them as they are decommissioned from their first life is a challenge we’re finding solutions for all the time.”

With the innovation at an early stage, reuse will focus on swapping steel for turbine blades in low stress structures such as temporary access roads, top sections of concrete walls and ground bearing plinths – like those on which a portacabin might sit.

Work on the proof of concept pilot is due to start in Spring 2021 and, if successful, could be followed by a full roll out across HS2’s London tunnels between the M25 motorway and Euston station.

Source: New Civil Engineer

Ancestral, but overshadowed by other technologies that have emerged over time, the rammed-earth walls are again gaining prominence in Brazil for being a low-impact, sustainable and economical solution. Known in Portuguese as taipa, it is a rudimentary construction system that compresses the earth into wooden boxes until it reaches an ideal density that allows a resistant and long-lasting structure.

Among the many benefits that rammed earth provides, its raw material is abundant, enabling the use of the same soil from the construction site, and reducing, therefore, the emission of carbon dioxide since it does not need long-distance transportation. In addition, it is non-toxic and provides a healthy environment in which the wall “breathes”, is fire resistant, and has excellent thermoacoustic insulation.

For example, in Arquipélago Arquitetos’s House in Cunha, the main walls are made from rammed earth. Using an authentic formwork system that avoids drilling and has developed a more efficient construction site, the modular components can be easily disassembled and reassembled. In addition, the rammed earth structures are tied by a concrete strap that serves as a support for the metal structure of the roof. The juxtaposed panels are solid enough to support the entire load weight of both the beam and roof.

Brazilian firm Argus Caruso decided to build the AA House, with rammed earth, in order to make the house breathe. Given the high humidity situation of Ubatuba, rammed earth could not be better. Employing several techniques, the foundation of the slab is in hyperadobe; the walls are built in the wattle-and-daub method and the structural wall is in rammed earth. For the architects, the top priority was to build a house with natural materials, ideally taken from the surroundings, but with a fine finish. The perfectly straight and smooth walls break the paradigm that a rammed-earth house is always crooked or badly completed.

All the soil generated by the earthmoving originated from the excavations of the foundations, can be used for the construction of rammed earth walls. In fact, this concept was used in the House in Mantiqueira, designed by Gui Paoliello in which the material was removed from the land itself and used in the foundation of three program-theme volumes (boxes) built with 30-cm thick (11.8-inches) earthen walls.

In the case of Guesthouse Paraty, designed by CRU! Architects, a 6.3-meter-long (21-feet-long) rammed red earth wall serves as soundproofing. As the site is on a slope, leveling was necessary. In this example, the raw material was also used with no extra energy required. In fact, the same formwork used for rammed earth was later applied to the roof structure.

Other features that architects seek to prioritize in the projects that adopt this ancient technique are color and texture. For example, at Estúdio OLO’s Casa Bosque, the orange rammed-earth structural wall works as an element that fits the intense chromatic palette of the project, which goes from the crimson kitchen to Sérgio Rodrigues’ Mole armchair in blue leather to the vibrant bookshelves at the end of the room.

Within the modern ways of adapting the use of rammed earth for the contemporary era, Casa Colinas features a unique system in the production of rammed earth structures with the use of metallic forms and the mechanization of the whole production process.

Source: Arch Daily

The benefits of modular construction are no secret – increased safety on site and schedule certainty, as well as less material waste and fewer delays. Yet, despite many within the industry calling for greater use, modular take up has remained slow and currently only accounts for a very small percentage of housing delivery.

However, the recent lockdown measures and all the subsequent restrictions put in place – along with the government’s ‘Build Build Build’ and ‘Green Industrial Revolution’ pledges – has seen greater emphasis placed on its utilisation as developers and housebuilders look for innovative solutions to deliver much-needed housing quickly.

Traditional housebuilding is still by far the primary build method in the UK, but the last few months have forced the wider industry to start thinking differently. The sector has looked at how they can innovate, adapt, and ultimately build more homes in the face of the pandemic.

The proportion of new homes built using MMC is therefore predicted to increase from the current 6-10% to 20% of the market share in the coming years, according to the last report from Savills. This is great news for the industry but in order to meet not only the UK’s housing delivery target but its aim of becoming carbon neutral by 2050 – this has to increase.

I believe the industry has been slow to accept MMC because it is largely misunderstood. There is a stigma around modular and a general hesitance to change as people are used to working in the traditional way. There is also a perception that the product is low quality and has no integrity of design, but that simply isn’t the case now.

There is a real lack of knowledge within the sector about modular and this reluctance to learn is stunting innovation and growth in the residential sector – and ultimately preventing us from quickly building more homes.

The pandemic has started to change this as developers and landowners are beginning to consider how to move forwards. For instance, we have started to see local authorities look towards modular building as a way to unlock residential sites to deliver affordable housing.

One such project that we’re currently working on is with Bassetlaw District Council alongside Faithful+Gould. The modular housing scheme is the first MMC project for the authority and will deliver 120 homes in Nottinghamshire.

We are responsible for looking at the flood risk, drainage, transport, and structural design as well as providing specialist MMC advice and the project marks our tenth modular scheme.

It’s therefore clear that more and more decision makers are waking up to the fact that modular housing is an incredibly viable option for a post-pandemic recovery. But we still need to go further.

Developments such as the one with Bassetlaw District Council help deliver modern, innovative and energy efficient residential schemes that improve neighbourhoods, support local jobs as well as the council’s ambition to increase its housing delivery.

However, we need it on a wider scale to really make a dent in the 300,000 new homes target set by the government. The scale of our work has definitely increased – from roughly ten units on a development to almost 700 on our most recent scheme – so I just hope we continue to see action rather than all the talk of pre-Covid times.

By Wayne Oakes is director at multi-disciplinary engineering consultancy Dice

Source: Civil Engineer

Hexagon Purus selected for hydrogen fuel cell project for construction equipment

Hexagon Purus will, for the first time, contribute to the development of zero-emissions equipment in the construction industry. Hexagon will deliver a 700 bar turn-key renewable hydrogen storage system for a demonstration project with a heavy equipment manufacturer to develop a fuel cell powered construction machine. The project will advance the understanding of the viability of hydrogen fuel cell power as a replacement for a traditional internal combustion engine to help reduce greenhouse gas emissions.

About the market
Unlike conventional diesel engine-based equipment, hydrogen-based electric construction equipment uses electricity produced through the chemical reaction between hydrogen and oxygen as its power source, meaning that there are no emissions of toxic gases or greenhouse gases into the air.

“The construction sector is undergoing a number of changes that could have a far-reaching impact. In the future, homes, offices and large infrastructure projects could be built using this zero-emission equipment,” says Todd Sloan, EVP Hexagon Purus Systems. “We are excited to enter this segment. We believe in clean air everywhere and we look forward to further projects to enable zero emission technology in the construction industry”.

About Hexagon Purus
Hexagon Purus, a Hexagon Composites company, is a world leading provider of hydrogen type 4 high-pressure cylinders, battery packs and vehicle systems integration for fuel cell electric and battery electric vehicles. Hexagon Purus enables zero emission solutions for light, medium and heavy-duty vehicles, buses, ground storage, distribution, maritime, rail, aerospace and backup power solutions.

Learn more at www.hexagonpurus.com and follow @HexagonPurus on LinkedIn and Twitter.